In medical facilities, nursing homes, and the like, a patient may leave his or her bed without a nurse or the like noticing that the patient has left, and an accident such as the patient wandering off and falling over may occur. To reduce the number of such accidents, there has been proposed a technology for detecting a movement of a patient regarding, for example, getting up from and leaving the bed.
For example, there is a technology for detecting the head of a person from images captured by a camera. With such a technology, for example, the head of a patient is detected from images captured by a camera installed at a position above a pillow on the bed, for example, directly above the headboard, and a getting-up movement or a bed leaving movement of the patient is recognized by tracking the detected head of the patient.
Japanese National Publication of International Patent Application No. 2006-511826 and Japanese Laid-open Patent Publication No. 2015-011649 are examples of related art.